Sink-shaft drill.



No. 879,822. PATENTED FEB. 18, 1908.

'- J. P. KARNS.

SINK SHAFT DRILL.

APPLICATION FILED MAR. 15. 1907.

2 SHEETS-SHEET 1.

' TYOR/VE VS No. 879,822. PATENTED FEB. 18, 1908. J. P. KARNS. SINK SHAFT DRILL.

APPLICATION FILED MAR. 15, 1907'.

, r 2 SHEETS-SHEET 2.

WITNESSES:

'5' 4 1 A TTORNE Y5 MEE srarr r rare,

, JOHN PRUE KARNS, OF BOULDER, COLORADO, ASSIGNOR TO THE J. P. KARNS TUNNELING MACHINE COL, OF BOUL'DER, COLORADO.

Sim-SHAFT BRILL.

No. e7a,e22.

v Specification of Letters Patent. Application filed March 15. 1907.. seen No. 362.533.

Patented Feb. 18, 1908.

To all whom it may concern:

Be it known that I, John PRUE KARNS; a: citizen of the United States, residing at Boulder, in the county of Boulder and State of Colorado, have invented a new-and useful Sink-Shaft Drill, of which the following is a specification This invention relates to drilling devices,- and has for its principal object to provide a mechanism of novel construction for the sinking of vertical shafts or wells oflarge di- 1 ameter through rock orother' material;

A further object of the invention is to provide a shaft sinking mechanism in which the drill head is free for rotative movement in order that the drill bits may strike againstiresh portions of thesurface at successive i movements, and in which the drill guidingdevices may serve as means for guiding and holding asand pump or'the like.

With these and other ob ects in view, as willmore fully hereinafter a pear, the invention consists in certain nove features of constructio and arrangement of parts, hereinafter ful y described, illustrated in the-accompanying drawings, and particularly pointed out in the appended claims, it being understood that various changes in the form, proportions, size and minor details of the structure may be made without departing from the spirit or sacrificing any of the advantages sired length and being provided at its upper end with any suitable means for attachment" to an o erating device, it being intended that the dri ling operation shall be accomplished by gravity, the drill head being of, such weight that whenraised and then allowed to drop, it will cut into the surface and reduce the rock or other material to fragments which can be'readil removed when mixed with water or the lihe.

On the lower face of the drill head are cutting bits 15, these being arranged so as to 'tions of the shanks oi the bits.

cover a very large area of the lower surface of;

the head, and a number of the bits being at ranged in a continuous annular series projecting' from the periphery of the drill head.

proper, these projecting bits being supported y radially disposed lugs 16 that are provided with dove tailed recesses 17 for the reception of the correspondingly shaped'norn will be seen that each bit may be readily slid into place with its dove tailed head fitting the dove tailedgroove, and when the parts are I thus locked together, it' will be impossible for the bit to drop from the horizontally disposed working face of the drill head.

ihe body of each drill head is provided with a horizontal slot 15 for the reception of thehorizontally turned lower end of an auxiliary securing bolt' 18 that passes upward through an opening in the drill head proper, and is'held in place by a'lockmg'nut 19,'or similar securing device, the object of this construction being toprevent longitudinal dis lacementoi the bit.

ecured to'the shaft 11 are two spaced collar 2 1' that preferably is formed of a'pair collar 21 are' 'radial arms 23 in the outer ends of which are formed small recesses for the rece tion' of the, inner ends of coiled compression springs 24, These springs" are mounted on radially projecting pins 25, the

inner endsoiwhich may slide in recesses inthe. arms are the outer portions of the said pins are threade d'ior the'reception of nuts26 which form bearings for the outer ends oif'the" 'the'nuts being adjustable in order to springs, A

it the nuts vary the stress of saidsprings.

the opposite direction, and in this manner the outward thrust exerted by the springs on" the stems 25 will be altered, as desired. The outer end'oi each arm or stem 25 is bifurcated and carries an anti-friction roller 28 that bears against the vertical wall of the shaft, the number of such rollers depending on the diameter of the drill head, four bein shown in the present instance. Thesevera outwardly extending arms 23 are connected by a strengthening rib 30, and the arms are further provided with lugs 31' from which so collars Y20, and between them is secured a of sections in order to permit convenient assemblingioi the parts. Extending from. the

'95" 26 are turned so that they approach the" shait'll, the springs Ztwill'be placed under greater stress than if. the nuts are turned in sinking shafts de end hanger bars 32 that are bolted or ot erwise secured to a ring 33 mounted on,

the drill head. p

It will be noted that the arms and stems are disconnected from each other at points beyond the rod 30, so that there are clear open spaces formed between the adjacent.

arms and the wall of the shaft'to ermit the insertion of the barrel of a sanc pum or similar mechanism for the purpose 0 removing the watcr and debris which passes through the open drill head.

I In operation, the drill is raised and then allowed to fall by gravity against the surface,

and the turning of the drill may be accomplished by slight twisting of the cable or other operating" deviceby which the drill is carried. The cable is twisted as the drill is pulled up, and the anti-friction rollers 28 will travel on slightly helical lines, on the wall of the shaft, the rollers moving freely removing the drill and without stopping the drilling operation. The sand pump barrel may be of the usual type, pointed at both ends, and in descending will'be guided between two adjacent arms 23 and supported during the vertical movement of the drill head.

ll. claim 2* lin a percussive drilling machine for large diameter, an open drill head carrying cutter bits on its lower face, a shaft extending upward from the center the drill head, a plurality of radially disposed arms projecting from the shaft at a point above the drill head, the outer ends of said arms being disconnected from each other to form clear aces for the admission oi-the barrel of a sa d pump or the like, and antifriction members supported by said arms and arranged to engage with the wall of the shaft being drilled.-

2. in percussive drilling mechanism. for sinking shafts large diameter, an open drill head having cutting bits on its lower face, a shaft connected to the head, a plusrasaa rality of arms radiating from the shaft at a point above the head, the outer ends of said arms being disconnected from each other to "form clear spaces for the admission of the ported by the arms, the outer endsof sald arms being disconnected and spaced from each other for the reception and support of a sand pump bucket.

4. In apercussive drillingmachine forsinking shafts of large diameter, an open drill head having a plurality of cutting bits on its lower face, a shaft extending upward from the center of the head, a collar rigidly secured to said head and provided with a plurality of radially extending recessed arms, the outer ends of which are disconnected to form free open spaces for the admission of a sand pump or the like, pins having their inner ends guided within said recesses, the outer portions of said pins being threaded, nuts mounted on the threaded portions ofthe ins com ressin sprin s dis osed between the nuts and the outer ends of the arms, and anti-friction rollers disposed at the extreme outer ends of said pins.

5. in percussive drilling mechanism for.

sinking shafts of large diameter, a drill head having dove tailed slots and provided with openings extending through the head, and cutting bits, each havinga dove tailed head arrange to Within the slot, each of the bits having an opening, and an auiriliary-se curing bolt for each bit, the bolt having a laterally bent arm arranged to engage 1n the opening in the bit shank, and an upwardly extending arm passing throughthe opening 'in the bolt.

drill head, and a securing nut on said in testimony that claim the foregoing as my own, i have hereto affixed my signature in the presence of two Witnesses.

- JQHN PRUE KARNS. Witnesses SZHIRLEY DAVIS, uno. 

